genode/repos/base/include/irq_session/irq_session.h

/*
 * \brief  IRQ session interface
 * \author Christian Helmuth
 * \author Martin Stein
 * \date   2007-09-13
 *
 * An open IRQ session represents a valid IRQ attachment/association.
 * Initially, the interrupt is masked and will only occur if enabled. This is
 * done by calling wait_for_irq(). When the interrupt is delivered to the
 * client, it was acknowledged and masked at the interrupt controller before.
 *
 * Disassociation from an IRQ is done by closing the session.
 */

/*
 * Copyright (C) 2007-2015 Genode Labs GmbH
 *
 * This file is part of the Genode OS framework, which is distributed
 * under the terms of the GNU General Public License version 2.
 */

#ifndef _INCLUDE__IRQ_SESSION__IRQ_SESSION_H_
#define _INCLUDE__IRQ_SESSION__IRQ_SESSION_H_

#include <base/capability.h>
#include <session/session.h>

namespace Genode {
	struct Irq_session;
	struct Irq_signal;
}


/**
 * Information that enables a user to await and ack an IRQ directly
 */
struct Genode::Irq_signal
{
	unsigned receiver_id;
	unsigned context_id;
};


struct Genode::Irq_session : Session
{
	/**
	 * Interrupt trigger
	 */
	enum Trigger { TRIGGER_UNCHANGED = 0, TRIGGER_LEVEL, TRIGGER_EDGE };

	/**
	 * Interrupt trigger polarity
	 */
	enum Polarity { POLARITY_UNCHANGED = 0, POLARITY_HIGH, POLARITY_LOW };

	/**
	 * Destructor
	 */
	virtual ~Irq_session() { }

	/**
	 * Await the next occurence of the interrupt of this session
	 */
	virtual void wait_for_irq() = 0;

	/**
	 * Get information for direct interrupt handling
	 *
	 * FIXME: This is used only client-internal and could thus be protected.
	 */
	virtual Irq_signal signal() = 0;


	/*************
	 ** Session **
	 *************/

	static const char * service_name() { return "IRQ"; }


	/*********************
	 ** RPC declaration **
	 *********************/

	GENODE_RPC(Rpc_wait_for_irq, void, wait_for_irq);
	GENODE_RPC(Rpc_signal, Irq_signal, signal);
	GENODE_RPC_INTERFACE(Rpc_wait_for_irq, Rpc_signal);
};

#endif /* _INCLUDE__IRQ_SESSION__IRQ_SESSION_H_ */